全文获取类型
收费全文 | 30380篇 |
免费 | 2962篇 |
国内免费 | 997篇 |
专业分类
耳鼻咽喉 | 306篇 |
儿科学 | 404篇 |
妇产科学 | 301篇 |
基础医学 | 1483篇 |
口腔科学 | 768篇 |
临床医学 | 5238篇 |
内科学 | 2376篇 |
皮肤病学 | 283篇 |
神经病学 | 2148篇 |
特种医学 | 797篇 |
外国民族医学 | 7篇 |
外科学 | 1959篇 |
综合类 | 4373篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 6569篇 |
眼科学 | 180篇 |
药学 | 3798篇 |
87篇 | |
中国医学 | 2531篇 |
肿瘤学 | 728篇 |
出版年
2024年 | 217篇 |
2023年 | 790篇 |
2022年 | 1327篇 |
2021年 | 1637篇 |
2020年 | 1649篇 |
2019年 | 1351篇 |
2018年 | 1292篇 |
2017年 | 1296篇 |
2016年 | 1313篇 |
2015年 | 1237篇 |
2014年 | 2314篇 |
2013年 | 2504篇 |
2012年 | 2051篇 |
2011年 | 2137篇 |
2010年 | 1573篇 |
2009年 | 1542篇 |
2008年 | 1412篇 |
2007年 | 1347篇 |
2006年 | 1131篇 |
2005年 | 895篇 |
2004年 | 781篇 |
2003年 | 674篇 |
2002年 | 515篇 |
2001年 | 473篇 |
2000年 | 379篇 |
1999年 | 354篇 |
1998年 | 294篇 |
1997年 | 219篇 |
1996年 | 217篇 |
1995年 | 176篇 |
1994年 | 177篇 |
1993年 | 140篇 |
1992年 | 129篇 |
1991年 | 110篇 |
1990年 | 94篇 |
1989年 | 77篇 |
1988年 | 79篇 |
1987年 | 58篇 |
1986年 | 57篇 |
1985年 | 71篇 |
1984年 | 57篇 |
1983年 | 29篇 |
1982年 | 25篇 |
1981年 | 21篇 |
1980年 | 31篇 |
1979年 | 18篇 |
1978年 | 22篇 |
1977年 | 13篇 |
1976年 | 7篇 |
1975年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
The differentiation of anxiety and depression by rating scales 总被引:1,自引:0,他引:1
62.
William G. Kohn Jonathan A. Ship Jane C. Atkinson Lauren L. Patton Philip C. Fox 《Journal of oral pathology & medicine》1992,21(2):70-74
Sequential salivary gland scintigraphy with 99mTc-technetium pertechnetate (Tc-99) is a safe, minimally invasive test for study of major salivary glands. However, its relationship to salivary function has not been investigated in detail. We have investigated the relationship between major salivary gland flow rates and Tc-99 scans and developed a new rating scale using scans of a control group with normal salivary function. Salivary flow rates and Tc-99 scans were obtained from healthy, non-medicated subjects (n = 33) and from xerostomic patients (n = 22). There were significant differences between the groups for salivary flow rates and Tc-99 ratings. Significant correlations were found between salivary flow rates and Tc-99 ratings in the control and xerostomic groups. The Tc-99 rating scale proved reliable in assessing salivary dysfunction, and showed a high inter-examiner correlation. These results demonstrate the usefulness of salivary gland scintigraphy in assessing major salivary gland flow rates and the utility of a new rating scale. 相似文献
63.
本文对肺部三种疾病1536例患者的病历资料,按病种作了统计归类。运用模糊数学原理建立了征候一疾病间的模糊关系矩阵,用参量加权模糊综合评判模型,对肺部三种疾病鉴别诊断的符合率达82.91%以上,因此认为文中建立的模型,对肺部三种疾病鉴别诊断具有参考价值。 相似文献
64.
Christina A. Burbeck 《Vision research》1992,32(12):2295-2302
Previous research has shown that separation discrimination thresholds are independent of the internal spatial scale (local spatial frequency) of the targets whose separation is being judged. The experiments reported here tested the generality of this conclusion for separation discrimination of targets that were embedded in an array of identical objects, where crowding could enhance the importance of the scale at which the individual target locations are encoded. No effect of the local spatial scale of the targets was found under these conditions. 相似文献
65.
Evaluation of allergenicity of genetically modified soybean protein extract in a murine model of oral allergen-specific sensitization 总被引:1,自引:0,他引:1
F. Gizzarelli S. Corinti B. Barletta P. Iacovacci B. Brunetto C. Butteroni C. Afferni R. Onori M. Miraglia G. Panzini G. Di Felice R. Tinghino 《Clinical and experimental allergy》2006,36(2):238-248
Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods. 相似文献
66.
酱油卫生状况模糊评价模型的建立 总被引:3,自引:0,他引:3
目前酱油卫生状况采用单项的评价方法,存在着轻重不分等不科学因素。如食盐超标与大肠菌超标及重金属超标有着极大的差别。为了消除这种差别,根据模糊数学原理、建立M(·+)综合评价模型[1]对宁德地区1989年酱油抽查检验结果进行卫生学评价取得了满意结果,从而为酱油卫生综合评价建立了有效的评价模型。 相似文献
67.
人胎盘提取组织凝血活酶及其质量评价 总被引:2,自引:2,他引:0
利用人胎盘抽提得组织凝血活酶,并对其质量进行了评价,同时初步应用于临床。结果显示:用含表面活性剂的抽提剂粉碎抽提的效果较好,所得组织凝血活酶重复性、灵敏度、稳定性均令人满意;与上海荣盛生物制品厂生产的PT试剂盒比较相关性好:Y=2.75+0.905x,r=0.9253,经相关系数t检验,t=26.5469,P<0.001,呈直线正相关。临床初步应用显示:肝病及抗凝治疗等病人PT时间明显延长,93例正常人x=11.3秒,s=0.96秒,正常范围9.42-13.18秒。 相似文献
68.
目的 对血液透析患者的几项营养指标进行评估。方法 依据SGA评分对142例维持性血液透析患者进行主观综合性营养评估(SGA)、膳食调查、生化参数的测量。结果 平均每日每公斤体重能量和蛋白质摄入(DEI、DPI)、血白蛋白,均有显著性差异(P〈0.001—0.05)。但营养良好组的DPI和DEI异常率高达49.0%、46.0%,重度营养不良组中各指标异常率均在80%以上。血前白蛋白与白蛋白有显著相关(P〈0.01),与DPI、DEI均无相关。结论 SGA是评价血透患者营养状况的简便方法,但还需其它反映营养状况不同侧面的指标的补充,如DEI、DPI、血白蛋白。前白蛋白作为血透患者营养监测的常规指标有待进一步证实。 相似文献
69.
孙志卿 《山西职工医学院学报》2003,13(4):5-6
目的 :评价阿奇霉素治疗支原体肺炎的临床疗效。方法 :对诊断明确的 5 2例支原体肺炎患者静滴阿奇霉素 5 0 0mg/d ,2d~ 3d 1次 ,疗程 10d~ 15d。结果 :痊愈 4 9例 (占 94 2 % ) ,显效 3例 (占 5 8% ) ,总有效率10 0 % ,体温正常时间 (3± 1 3)d。结论 :阿奇霉素治疗支原体肺炎临床疗效肯定 ,使用安全方便 相似文献
70.
检测幽门螺旋杆菌感染的几种方法的比较 总被引:5,自引:0,他引:5
目的 :评价几种诊断幽门螺杆菌 (Hp)感染的检测方法 .方法 :对 386例患者行胃镜钳取胃窦粘膜 ,分别经改良Giemsa染色、快速尿素酶 (RUT)试验、14 C 尿素呼气试验 (14 C UBT)检查及HpIgG血清学检查 ,与细菌培养结果对照 ,用 χ2检验进行对比评价 .结果 :RUT ,14 C UBT和改良Giemsa染色的敏感性、特异性较高 ,与细胞培养的符合率相近 ,其中14 C UBT和改良Giemsa染色联合检测的符合率更相近 (99.7% ) ;HpIgG血清学检查的敏感度虽和其余检测方法无差别 ,但其特异度较低 ,尤其是复诊组的特异度 ,与其他检测方法有显著差异 (P <0 .0 1) ,而且与初诊组相比也有差异 (χ2 =35 .18,P <0 .0 1) .结论 :HpIgG血清学检查可用于Hp感染的筛查 ,而不能作为疗效判断的指标 ,14 C UBT和改良Giemsa染色联合检测是较可靠的Hp检测方法 相似文献